Relay system can improve the secrecy of a wireless communication with physical layer security algorithms.Most of these algorithms include two stages:during the first stage, the source node sends coded messages to the relays, and during the second stage, the relays forward the received messages to the destination node.Usually, there is no protection during the first stage, thus most of the secrecy analysis is based on the assumption that there is no direct channel between the source and the eavesdropper.In a practical system, when the eavesdropper is located near the source, the secrecy rate of all these algorithms is down to zero.In this paper, a novel three-stage algorithm with hybrid signals is proposed, which can offer full protection on a relay system.The algorithm results in a non-convex optimal problem, and a sub-optimal solution with low computational complexity is proposed.The theoretical analysis and simulation results show that the proposed scheme can achieve much better secrecy performance than traditional algorithms when the eavesdropper is near the source node.
杨斌, 王文杰, 殷勤业. 基于混合信号的放大转发中继系统的物理层安全传输[J]. 电子学报, 2016, 44(2): 268-274.
YANG Bin, WANG Wen-jie, YIN Qin-ye. Secure Wireless Communication for AF Relay System with Hybrid Signals. Chinese Journal of Electronics, 2016, 44(2): 268-274.
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